Chimney



June 18, 194@. F BEEBY 2,204,955

CHIMNEY Filed Nov. 6, 1939 INVENTOR fA/VK F 52-55 Y.

QMXZM 22 ATTORNEY fill Patented June 18, 1940 UNITED STATES PATENT OFFICE CHIMNEY Frank F. Beeby, River Forest, 111., assignor to Cement Gun Company, a company of Dela.-

ware

Application November 6, 1939, Serial No. 302,955

6 Claims.

gate, is blown through a hose and a suitable nozzle, where it is hydrated, against a suitable backing. The Gunite thus formed is dense and strong.

Heretofore, it has been proposed to repair a chimney such as steel chimney or stack, by surrounding the chimney to be repaired with a layer or coating of compressible material, such as{ asbestos, which is heat resistant and heat insulating, and by forming against said compressible material an outer reenforced chimney of suitable material such as Gunite. In this way there is built about an already existing chimney a second complete chimney independent of the original chimney so that the original chimney may be completely destroyed without in any way aifecting the outer chimney which remains and serves the same general purpose as the original chimney. The layer of compressible insulating material serves to space the outer chimney fromthe inner chimney or stack and serves not only as a cushion to permit expansion of the inner stack or chimney Without cracking the outer chimney or shell, but

as heat-insulation to protect the outer chimney from heat which might cause cracking of the Gunite, particularly during the setting thereof.

The gases passing through the steel stack produce an acid action on the steel even where the stack is lined with brick and this action may be intensified when the steel isencased in an outer chimney of Gunite, with the result that the steel plates will go to pieces quite rapidly. When the steel plates break down, the asbestos layer may also lac-broken and its heat insulating efiect lost to a cerdtain extent. Furthermore under some conditions the insulation of the asbestos layer as usually formed might not be sufficient. Consequently the conclusion was reached that it would be wise to construct the outer stack to increase its protection from heat and also to provide for protection against acid penetration and action.

An important object of the present invention is to provide improvements in chimney construction of the character wherein a separate chimney of suitable material, such as Gunite" is built around another chimney to strengthen the same and assist in giving effective service, and in the event of destruction of the original inner chimney the outer chimney may function by itself.

According to one manner of carrying out the present invention, a compressible layer or coating of heat-resistant and heat-insulating material, such as asbestos is applied, as heretofore, to the outside of the chimney to be repaired, but, instead of constructing the outer reenforced chimney of Gunite or the like as heretofore, there is applied a relatively thin layer of heat resistant and heat-insulating material made of a relatively fine aggregate having the requisite heat resisting and heat insulating qualities, and cementitious material adapted to meet the above-mentioned requirements as to heat resistance and insulation, and then the rest of the outer chimney is constructed of Gunite in the same, general manner as heretofore, thus providing a unitary outer chimney.

One kind of cement that meets the aforesaid requirements for the inner layer of the outer chimney is Lumnite cement which is a calcium alumnate cement as distinguished from Portland cement in which the principal constituents are calcium silicates. Lumnite is of particular value in that its effectiveness as a binder is not destroyed by high service temperatures. The aggregate for use with Lumnite or other suitable cement, may be of any suitable material, such as sand, but preferably is of material, highly resistant to heat and acid action, such as ground trap rock or Haydite, which possesses such qualities to a marked extent. The mixture of Lumnite cement and granular aggregate may be applied by suitable apparatus, such as a Cement Gun}? and as soon as a layer of sufficient thickness has been formed the usual Gunite may be applied to the outside thereof until the necessary thickness is attained. The outer chimney will then have at its inner surface material which is resistant to acid and heatand also is heat insulating, thereby serving to protect the Gunite of the outer chimney. Obviously the outer chimney constructed in this manner will be much superior to those constructed heretofore.

Other objects, features and advantages will appear upon consideration of the following detailed description and of the drawing in which the figure is a fragmentary elevation of a chimney embodying the invention, parts being broken away to show the interior structure.

In the drawing there is a fragmentary showing of a suitable foundation or supporting structure I0 to which the enlarged base of a steel chimney or stack I I is secured. When a steel chimney or stack such as chimney II becomes weak or leaks or becomes defective for other reasons, it may be repaired by building therearound a suitable outer chimney I2. According to prior practice the chimney or stack II to be repaired may be covered with a compressible layer or coating I3 of suitable material, such as asbestos, Which is heat-resistant and heat insulating and outside of such compressible layer there may be constructed an independent outer chimney.

Heretofore such an outer chimney has been of reenforced Gunite and the only protection thereof has been furnished by said compressible layer or coating I3 which has also acted to prevent cracking of the outer chimney due to expansion of the stack or chimney II. The protective layer I3 of the usual thickness may not give sufficient protection for the outer chimney I2 when the inner chimney I I is very hot and in any event the acid in the gases passing through the inner stack may gain access to the inner surface of the outer stack and if this stack be of Portland cement Gunite only, the acid might cause considerable damage at the inner surface thereof.

Therefore in carrying out the present invention, the outer chimney may be made. principally of Portland cement Gunite as heretofore but at its inner side is provided with a protective layer I l of material which is not only heatinsulating and heat resistant but is resistant to acid action. Preferably the material of said layer I4 is applied in the same manner as Gunite and is formed from a suitable mixture of cement, such as Lumnite which is heat and acid resistant as well as heat insulating, and granular material, such as ground trap rock or Haydite.

In constructing the outer chimney I2, the inner original chimney II is covered with the compressible coating l3 of asbestos, and in connection with the placing of suitable reenforcing material, the protective layer it may be placed by a Cement Gun and when the layer I4 has reached the requisite thickness, it may be used as a backing and Gunite placed thereagainst until the wall of the outer chimney I2 has been brought 50 the required thickness. Obviously the layer It will be integral with the Gunite layer I5 at the outer side thereof. a

The reenforcement of the outer chimney may be effected in any suitable manner and as illustrated includes wire mesh I6 for the protective layer I 4, wire mesh IT for the Gunite I5 and heavy reenforcing material for the outer chimney comprising rods I 8 extending longitudinally of the chimney and rods I9 extending circumferentially of the chimney. In order to anchor the outer chimney I2 to the base or foundation ill, the rods I8 may pass through openings in an outwardly extending flange of a horizontally positioned flange ring 20 and be secured thereto by nuts 2I on these rods above and below said outwardly extending flange, and the rods I8 may be held with their lower ends resting on the outwardly extending base of the inner chimney II by bolts 22 passing through the foundation If], the base of the chimney II and clips or brackets 23 attached to the downwardly extending flange of the ring IS. The bolts 22 may be positioned inthe same manner as the usual ney engaging the outer surface of said layer of compressible material, said outer chimney comprising an inner dense heat-resisting and heatinsulating layer of fine granular material resistant to heat and acids and heat-resistant cementitious material, and a thick dense body of sand and cement at the outside of such inner layer and integral therewith.

2. A double chimney comprising an inner chimney, a layer of compressible heat resistant and heat insulating matter covering the outside surface of the inner chimney, and an outer chimney engaging the outer surface of said layer of compressible material, said outer chimney comprising an inner dense heat-resisting and heat insulating layer at the inner surface thefeof consisting of fine granular material resistant to heat and acids and heat-resisting cementitious material, and a body of Gunite at the outer side of such inner layer and integral therewith.

3. A double chimney comprising an inner chimney, a layer of compressible heat resistant and heat insulating matter covering the outside surface of the inner chimney, and an outer chimney engaging the outer surface of said layer of compressible material, said outer chimney com prising an inner dense heat-resisting and heatinsulating layer of fine granular material resistant to heat and acids and Lumnite cement, and a dense body of Portland cement Gunite at the outer side of said inner layer and integral, therewith.

4. The method of constructing a second chimney about a chimney already in place, comprising covering the outer surface of the first chimney, already in place, with a compressible layer of heat-resisting and heat-insulating material, blowing into place against the outer face of said layer of compressible material a mixture, hydrated just before application, of heat-insulating and heat-and-acid-resisting cementitious material and granular material thus forming an inner layer of the outer chimney, and placing a relatively thick layer of Gunite at the outer side of said inner layer and integral therewith.

5. The method of constructing a second chim ney about a chimney already in place, comprising covering the outer surface of the first chimney, already in place, with a compressible layer of heat-resisting and heat-insulating material, blowing into place against the outer face of said layer of compressible material a mixture, hydrated just before application, of heatinsulating and heat-and-acid-resisting cementitious material and granular material having to a certain degree the same resistant qualities, thus forming an inner layer of the outer chimney, and blowing against the outer surface of said inner layer a mixture of sand and cement hydrated immediately before application thus forming an integral outer chimney.

6. The method of constructing a second chimney about a chimney already in place, comprising covering the outer surface of the first chimney, already in place, with a compressible layer of heat resisting and heat-insulating material,

blowing into place against the outer face of said layer of compressible material a mixture,

hydrated just before application, of heat-insulating and heat and acid resisting Lumnite cement and granular material which has the same general resistant qualities, thus forming an inner layer of the outer chimney, and applying a relatively thick third layer of Gunite at the outer side of said inner layer so as to be integral therewith.

FRANK F. BEE-BY. 

